A shekara ta 1949, sojojin 'yantar da jama'ar Mao Zedong sun fatattaki gwamnatin Chiang Kai-shek ta
Amurka mai goyon bayan Kuomintang (KMT) a kasar Sin.KMT ya koma
Taiwan .Nan take Kremlin ta kulla kawance da sabuwar
jamhuriyar jama'ar kasar Sin .A cewar masanin tarihin kasar Norway Odd Arne Westad, 'yan gurguzu sun yi nasara a
yakin basasar kasar Sin saboda sun yi kurakuran soja kadan fiye da yadda Chiang Kai-Shek ya yi, kuma saboda a kokarinsa na neman kafa gwamnatin tsakiya mai karfi, Chiang ya yi adawa da kungiyoyin masu sha'awa da yawa a kasar Sin.Bugu da ƙari, jam'iyyarsa ta raunana a lokacin yakin da aka yi da
Japan .A halin da ake ciki, 'yan gurguzu sun gaya wa kungiyoyi daban-daban, irin su manoma, daidai abin da suke son ji, kuma sun lullube kansu a karkashin tsarin kishin kasar Sin.An fuskanci juyin juya halin gurguzu a kasar Sin da kuma kawo karshen ikon mallakar makaman nukiliya na Amurka a shekarar 1949, gwamnatin Truman ta yi sauri ta kara habaka da fadada rukunan ta.A cikin NSC 68, daftarin sirri na 1950, Majalisar Tsaro ta Kasa ta ba da shawarar karfafa tsarin kawancen kasashen yamma da kuma rubanya kashe kudade kan tsaro.Truman, a ƙarƙashin rinjayar Paul Nitze mai ba da shawara, ya ga ɗaukar hoto yana nuna cikakkiyar jujjuyawar tasirin Soviet a kowane nau'i.Jami'an Amurka sun matsa don fadada wannan juzu'i na kayyadewa zuwa Asiya, Afirka, da Latin Amurka, don fuskantar yunƙurin juyin juya hali na kishin ƙasa, waɗanda galibin jam'iyyun gurguzu da Tarayyar Soviet ke jagoranta, suna yaƙi da maido da daulolin turawan mulkin mallaka a Kudu maso Gabashin Asiya. da sauran wurare.Ta wannan hanyar, wannan Amurka za ta yi amfani da "mafi girman iko," adawa da tsaka-tsaki, da kuma kafa mulkin duniya.A farkon shekarun 1950 (wani lokaci wani lokaci ana kiransa "Pactomania"), Amurka ta tsara jerin ƙawance tare da Japan,
Koriya ta Kudu ,
Taiwan , Australia, New Zealand,
Thailand da
Philippines (musamman ANZUS a 1951 da SEATO a 1954) , ta yadda zai ba wa Amurka garantin sansanonin soji na dogon lokaci.